From: Misael Lopez Cruz <misael.lopez@xxxxxx>
Enable the burst and data pack modes for the scatter-gather
in order to improve the throughput of the data transfers.
The improvement has been verified with MMC HS200 mode in
the DRA72 EVM using the iozone tool to compare the read
throughput (in kB/s) with and without burst/pack for
different reclens (in kB).
With
reclen Baseline sDMA burst/pack
------ -------- ---------------
64 46568 50820
128 57564 63413
256 65634 74937
512 72427 83483
1024 74563 84504
2048 76265 86079
4096 78045 87335
8192 78989 88154
16384 81265 91034
Signed-off-by: Misael Lopez Cruz <misael.lopez@xxxxxx>
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@xxxxxx>
---
drivers/dma/omap-dma.c | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)
diff --git a/drivers/dma/omap-dma.c b/drivers/dma/omap-dma.c
index 1b7f5f32bf74..7ca27d4b1c54 100644
--- a/drivers/dma/omap-dma.c
+++ b/drivers/dma/omap-dma.c
@@ -904,13 +904,16 @@ static struct dma_async_tx_descriptor *omap_dma_prep_slave_sg(
d->es = es;
d->ccr = c->ccr | CCR_SYNC_FRAME;
- if (dir == DMA_DEV_TO_MEM)
+ if (dir == DMA_DEV_TO_MEM) {
d->ccr |= CCR_DST_AMODE_POSTINC | CCR_SRC_AMODE_CONSTANT;
- else
+ d->csdp = CSDP_DST_BURST_64 | CSDP_DST_PACKED;
+ } else {
d->ccr |= CCR_DST_AMODE_CONSTANT | CCR_SRC_AMODE_POSTINC;
+ d->csdp = CSDP_SRC_BURST_64 | CSDP_SRC_PACKED;
+ }
d->cicr = CICR_DROP_IE | CICR_BLOCK_IE;
- d->csdp = es;
+ d->csdp |= es;
if (dma_omap1()) {
d->cicr |= CICR_TOUT_IE;
--
2.10.0
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